A multiple access wireless network generally includes a number of geographically spaced base stations for providing network coverage over a geographical area. A number of user equipments located in the area communicate over the network via at least one of the base stations. The base stations may each have one or more partitions, formed by a combination of sectors and/or beams.
Generally, the channel gains for the radio links between the user equipments and all base station partitions are considered. Then each user equipment communicates with a parent partition selected to be that partition with the radio link to the user equipment having the highest channel gain. Thus, each base station partition will then have a number of child user equipments with which it communicates.
Each partition generally has a finite spectral resource over which it can communicate with its child user equipments. Conventionally, each user equipment is allocated an amount of spectral resource, e.g. one or more channels in a FDMA (Frequency Division Multiple Access) system, or a predetermined sub-set of timeslots in a TDMA (Time Division Multiple Access) system. In the conventional system, the spectral resource of a parent partition is shared equally among all its child user equipments and all spectral resource is reused at every partition (ie. N=1 re-use). Therefore, the number of resource units allocated to a child user equipment is dependent on the number of other child user equipments in that partition and so the number of resource units allocated to the child user equipments varies from partition to partition.
The uplink transmit power at which each user equipment transmits radio frequency signals is conventionally arranged so that user equipments experiencing a high gain transmit with a lower power so as to reduce interference to other cells.
In prior art systems there are generally many (ie. hundreds) of user equipments per partition and so the network load per partition does not vary much across the network. More recently, networks are supporting higher data rates (eg. for video streaming, etc.). A partition can support fewer simultaneously transmitting user equipments at higher data rates, which means that the variation in network load per partition becomes more varied. This variation can significantly effect the performance of the network.
Future wireless networks aim to provide increasingly higher rate services to an increasing number of users. Spectral resource is a limited and costly resource and so increasing the efficiency of the usage of spectral resource will become more and more important.